Grulke et al U.S. Pat. No. 5,046,486, assigned to the assignee of the present invention, discloses a suction-irrigation handpiece including a forward extending, elongate wand comprising irrigation and suction tubes, through which, respectively, a pulsed irrigation liquid is applied to a surgical site and flowable materials are suctioned from the surgical site. This device has been marketed by the present assignee, Stryker Corporation, of Kalamazoo, Mich., under the trademark EXCEL.
The EXCEL (TM) device has been sold with a straight cylindrical irrigation outlet flow port. In addition the EXCEL (TM) device has been sold with a modified tip member in which the irrigation outlet flow path is blocked by a coaxially close spaced pair of radially extending disks each having four, evenly circumferentially spaced, axial through holes. The forward disk is angularly offset through 45.degree., about the common axis of the two disks, with respect to the rearward disk, so that irrigation flow through the holes in the first disk hits the forward disk between the holes therein, filling the space between the disks with a circumferentially turbulent mass of irrigation liquid, from which liquid eventually escapes through the circumferentially offset holes in the forward disk. The result is a substantially solid cross-sectional flow of conical profile, forward from the forward disk or, in other words, a substantially solid, forwardly travelling, radially diverging, solid stream. With such tip member used with the EXCEL (TM) handpiece, such stream is axially broken into a series of axially substantially discrete, generally disk-like slugs, or pulses. This tip member tends to reduce the force of impact of each liquid pulse on the surgical site, and spread same over a larger area, and substantially reduces the irrigation liquid flow rate to the surgical site (substantially reduces the irrigation liquid delivered per unit time at the surgical site).
The present assignee also markets an improved pulsed irrigation-suction handpiece, capable of more forceful, sharply defined, irrigation liquid pulses, under the trademark SURGILAV PLUS.
In both of the above-mentioned suction-irrigation handpieces, the suction and irrigation tubes are coaxially telescoped and form a removable wand which extends forward from the housing of the handpiece. The irrigation liquid tube is of lesser diameter than, and is coaxially disposed within the larger diameter suction tube. The tubes are radially fixed one within the other, with an annular suction passage radially between the two, by structure at the proximal and distal ends of the tubes. The structure at the distal ends of the tubes comprises circumferentially spaced, radially extending fins extending radially outward from the distal end of the irrigation tube to engage the interior surface of the suction tube. The handpiece is actuable by a surgeon, or surgical assistant, to forcibly forwardly expel pulses of irrigation liquid from the distal end of the irrigation tube and to suction a flowable material from the surgical site, into the distal end of the suction tube and thus into the annular space surrounding the irrigation tube.
The SURGILAV PLUS (TM) device is capable of unusually forceful, sharply defined irrigation liquid pulses and is thus particularly effective for difficult surgical site cleaning jobs wherein unwanted bits of tissue or the like may be difficult to remove from surfaces at the surgical site. For example, the SURGILAV PLUS (TM) device has been found particularly effective in cleaning bits of soft tissue out of a femoral cavity in preparation for cementing therein of the elongate, ball-supporting stem of a hip joint prothesis.
However, the present Applicant has noted that use of the same suction-irrigation handpiece for medical/surgical procedures with substantially different requirements (for example in terms of force and pattern of irrigation liquid output from the handpiece), would help limit increase of medical costs to the public, for example by limiting the number of different types of suction-irrigation handpieces needed to be designed, manufactured and inventoried by suppliers and bought and inventoried by medical practitioners.
Applicant has further noted that it is in some instances desirable to use multiple, narrow, discrete streams of irrigation liquid pulses to tissue at the full force capability of the handpiece, e.g. the SURGILAV PLUS (TM) handpiece. Such streams have length axes which are skewed with respect to each other, so as to cross each other in laterally spaced relation. Such streams angle away from the central axis of the irrigation tube. Such angled, pulsed streams can more easily be directed at an acute angle to a surgical site surface without having to angle the irrigation tube and handpiece. Such angled, pulsed streams also can dislodge debris from a surgical site surface by a kind of chiseling action, i.e. by digging laterally under debris and prying it off the surgical site surface. An example is the cleaning of debris from the tibial plateau in knee surgery. However, Applicant notes that it is desirable to avoid reduction in flow rate (unit volume per unit time) of irrigation liquid to the surgical site.
Accordingly, the objects and purposes of the present invention include provision of a tip member for a surgical irrigation wand for varying the nature of irrigation liquid flow from an irrigation handpiece, particularly to adapt to multipoint angled cleaning of surgical sites.